The term “Sophist,” though in its original and wider sense it was applied to the professors of philosophy generally, had come to mean, in the popular language of Athens, those who, for pay, undertook to teach a method of rhetoric and argument by which a man might prove anything whatever. It is against these public lecturers, who either taught or were commonly believed to teach this perversion of the great science of dialectics, that Aristophanes brings the whole weight of his biting humour to bear in ‘The Clouds.’ This is no place to inquire how far the accusation brought against them was or was not a fair one, or whether that abuse of their powers which was the disgrace of a few may not have been attributed by unjust clamour to a whole class of public teachers in which they were but the exceptions. It is possible to believe not only, with Mr Grote, that the Sophists “bear the penalty of their name in its modern sense,” but also that in their own day they bore the penalty of superior ability and intelligence in becoming the objects of dislike, and therefore of misrepresentation, and yet to understand how they may have afforded very fair material for the professional satirist. The art of public speaking, which these professors taught, is a powerful engine, which in unscrupulous hands may do as much to mislead as to instruct. That the love of disputation and the consciousness of power will tempt a clever man to maintain a paradox, and discomfit an opponent by what he knows to be a fallacy--that a keen intellect will delight in questioning an established belief--and that the shallow self-sufficiency of younger disciples will push any doctrine to its wildest extremes,--are moral facts for whose confirmation we have no need to go to ancient history. And we are not to suppose that either the poet or his audience intended the fun of the piece to be taken as serious evidence either of the opinions or the practice of any school whatever.